Toma, G., P. Onorati, G. Bellagamba, M. Vernetti Prot, and T. Lupattelli. “The Intra and Extra Cranial Veins in Relationship With Chronic Migraine”. Veins and Lymphatics, vol. 8, no. 1, Aug. 2019, doi:10.4081/vl.2019.8435.